This proposal requests funds to enable young investigators in training to attend the 18th International Herpesvirus Workshop to be held in Pittsburgh, Pennsylvania July 25-30, 1993. This workshop is the most important meeting for investigators in the herpesvirus field. It is the forum where the most recent advances in the field are first presented. This meeting also provides an opportunity for new graduate students and postdocs to obtain an appreciation for the scope, complexity and current state of knowledge of the Herpesvirus field. The strength of this workshop results from the high level of participation by investigators in all areas of herpesvirus research. The meeting is attended by researchers from all over the world with both basic and clinical interests. The broad based interests of the participants results in the cross-fertilization of individual research programs and also provides an atmosphere that encourages the exchange of new information. Herpes viruses cause a wide range of diseases in humans. Herpes simplex viruses types 1 and 2 (HSV-1, HSV-2) cause skin, eye and genital ulcerations. Varicella-zoster virus (VZV) causes chicken pox and shingles, while Epstein-Barr virus (EBV) is responsible for infectious mononucleosis. Congenital infection with HSV-2 and cytomegalovirus (CMV) are significant causes of mental retardation, while HSV encephalitis can be fatal. HHV 6 has been associated with a febrile illness in infancy resembling exanthem subitem. HHV 7 has recently been isolated from healthy individuals. Neoplasias such as nasopharyngeal carcinoma, B-cell lymphoma, and Hodgkins disease are all associated with EBV. Several members of the herpesvirus have been identified as possible cofactors in the growth and pathogenesis of human immunodeficiency virus. The hallmark of herpesviruses is the ability to establish a latent infection, persist in the host for years and subsequently reactivate, causing disease. Due to this property, herpes viruses are opportunistic infectious agents contributing to morbidity and mortality in the immuno- compromised. Organ transplant recipients and AIDS patients are susceptible to EBV associated systemic, central nervous system and oral infection, CMV retinitis and pneumonitis, and disseminated CMV, VZV and HSV infections. An emerging area that takes advantage of this aspect of herpesviruses is the development of modified herpesviruses for gene transfer purposes. Animal herpesviruses have significant economical importance to the poultry (Marek's Disease Virus), swine (pseudorabies virus), dairy (bovine rhinotracheitis virus) and equine herpesvirus) industries. Sessions will be convened to discuss the following topics: gene regulation, DNA replication, genome structure, enzymes and non-structural proteins, glycoproteins and structural proteins, receptors and virus entry, transformation and neoplasia, immunology, viral pathogenesis, viral vectors, anti-virals and resistance, vaccines and therapy.